Temperature Gauge MFA Rev Counter

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whiteshark
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Temperature Gauge MFA Rev Counter

Post by whiteshark » Tue Sep 22, 2020 11:16 pm

My temperature gauge has never worked, ever, period since I bought the car. The light on it would flash if I was running slightly low on water and a very small top up would cure the issue. There has been a new water pump fitted and some samco hoses added. I've also recently fitted a new radiator and the light has not been on since.
I have installed a new temperature sensor on the engine block and I took out the speedo dials / cluster and replaced the three pin chip on the back of the speedo that can cause issues with the temperature gauge, but no joy. Any suggestions or just change the temperature gauge?

MFA, My MFA was working but was heavily bleeding. I replaced this but now only one of the numbers are visible and the rest are gobbly gook and only partly displayed. The replacement LED was second hand, should I just buy a new one or have I screwed on the replacement LED too tightly?

Rev Counter: I'm running a KR 16V engine. Would an American REV counter fitted to an American 16v left hand drive which goes RED from the 7-8 thousand REVS fit my Right Hand drive Speedo instrument Cluster?

Any advice welcome as my kitchen table time and my wife's patience is very limited. If I have the Instrument cluster out again I would like to get everything sorted, quickly and not spend the day again removing interior panels and having several small screws on the kitchen table. The REV counter with the 8 thousand limiter and Unleaded fuel only display would be a Brucie bonus. More interested in having the water temperature gauge working.

Any suggestions welcome.



Kdc169
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Re: Temperature Gauge MFA Rev Counter

Post by Kdc169 » Wed Sep 23, 2020 7:44 am

Che ck you have earth to rocker and earth from coil is good .. try disconnect battery to reset mfa.



mark1gls
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Re: Temperature Gauge MFA Rev Counter

Post by mark1gls » Tue Nov 03, 2020 10:28 pm

My temperature gauge is also temperamental, it works 1 times out of 10 and have found this info on fixing it but never got around to doing it..

Have a read here...

http://www.toplessrabbit.com/forums/vie ... =27&t=2042


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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whiteshark
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Re: Temperature Gauge MFA Rev Counter

Post by whiteshark » Tue Nov 24, 2020 10:23 pm

Thanks Mark, going to give this a blast at the weekend. If the 9v does nothing I have other gauges I can strip and replace the sender with. Nice to know the actual names of the chips. When I chat to my mechanic he just says have a go at this Phil and points to various bits. I can now fill him in with the correct names!



PeteGLi
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Re: Temperature Gauge MFA Rev Counter

Post by PeteGLi » Thu Nov 26, 2020 5:19 pm

Before taking it all apart, check that the terminal on the single wire coloured Yellow/Red which runs from the temperature sender into the wiring harness is securely connected, as the wire can corrode and break at this point. Replace the terminal if necessary.
Then, with this Yellow/Red wire disconnected from the sender, turn the ignition to 'ON' but without starting the engine. The gauge needle should remain on its stop, and not move.
With the ignition key still turned to ‘ON’, using a suitable jumper lead, connect the Yellow/Red wire to earth, either via the battery negative terminal, or to the engine (rocker cover stud).
The gauge needle should now move to the right and show ‘Hot’ and the warning light should flash.
Turn the ignition key off and reconnect the Yellow/Red wire to the sender.
If the gauge works as indicated above, with the wire disconnected and earthed, but does not work when connected to the sender, then the sender is at fault and should be replaced.
If the gauge needle moves off its stop and indicates any reading at all, when the wire to the sender is disconnected but NOT earthed, then either the gauge is defective or there is a short to earth somewhere in the wiring.